Cassandra said:
Yeah, I thought so. I think some fruits (like apples I have heard) have more pectin in them than others, so some fruits don't need pectin to make jelly. But I would be scared to try to make jelly without it...
Apples are a nice trick to thickening some things, because of their pectin.
When I make cranberry sauce, I always put a couple of apples in, with seeds and skins. (If I want a lot of work, I drop apple quarters in, then later fish them out and remove meat from skin, and reincorporate the meat. Older and wiser has me peeling the apple etc. and putting the skins and such in cheese cloth, and the meat in with the berries. Just fish out cloth bag when done; squeeze, voila!)
That's how my grandmother made it, and it also had a pleasant mellowing effect for the flavor. You can just use baking apples for a pleasant, mellow flavor, but I like to use apples with interesting flavors to add to the final product. I use the old variety, Blushing Darlings off our tree. There's nothing exactly like it in the store, but Pink Ladies, which are available at Thanksgiving, are a good bet.
Mostly I make jam, pancake syrup and ice cream/angelfood cake etc. toppings with the blackberries we don't use for fresh eating, cobblers, pies, ice cream, sorbet etc. I used to make jelly from them, but decided that jam was great, and easier! I still do make jellies from mint, and some of the grapes, though. (Also grape jam.)
Good luck; I hope you have enough for a pie, and maybe a cobbler!
